Bakgrund: Bröstcancer är den vanligaste cancerformen hos kvinnor i Sverige. Riskfaktorerna är flera och därför har Socialstyrelsen bestämt att hälso- och sjukvården ska erbjuda mammografiscreening för att upptäcka sjukdomen i ett tidigt stadium. Bukaortaaneurysm är en lokal vidgning av kroppspulsådern som främst drabbar män. Sjukdomen är ofta asymtomatisk och kan vara livshotande. Socialstyrelsen har därför bestämt att en engångsundersökning ska erbjudas alla män i 65-års ålder. Syfte: Syftet med examensarbetet var att studera anledningar till utebliven screeningundersökning och om anledningarna skiljer sig åt för mammografi- och bukaortascreening. Metod: Detta examensarbete är en litteraturöversikt som behandlar 15 vetenskapliga artiklar relevanta till arbetets syfte. Resultat: Faktorer som påverkade deltagandet var: ålder, invandring, nära relation till sjukdomen, avstånd, svårigheter att ta sig till klinik/opassande öppettider, utbildning, social status, fysisk och psykisk ohälsa, okunskap/bristande information, rädslor/förnekelse, civilstånd/familj och mottagen påminnelse. Diskussion: Samtliga punkter för icke deltagande stämde inte alltid överens för de båda screeningprogrammen. Efter granskning av inbjudan till screeningprogrammen sågs skillnader i informationen som skulle kunna ha betydelse för de faktorer som studerats i artiklarna. Slutsats: Icke deltagande kan bero på flera faktorer som påverkas av varandra och en liten skillnad mellan män och kvinnor sågs. Inbjudan kan påverka deltagandet i vissa fall. / Background: Breast cancer is the most common form of cancer in women in Sweden and there are several risk factors. Abdominal aortic aneurysm is an expansion of the vessel and men are most likely to suffer. The disease is asymptomatic and life-threatening. The National Board of Health and Welfare has decided to offer mammography screening and aneurysm screening to detect the diseases in an early stage. Aim: The aim with this review was to study reasons for non-participation in screening and if reasons differ from the both screening programme. Method: This bachelor thesis was designed as a review based on 15 articles. Results: Factors that affect the attendance was: age, immigration, close relations to the disease, distance, disable to get to the clinic/unfitting opening hours, education, social status, physical/mental health, unknowledge/less information, fear/denial, civil status/family and reminder letter. Discussion: Factors for non-attendance was not the same for both screening programmes. Inspection of the invitation letter from Jönköping county showed some defects that could affect the factors that has been found in the articles. Conclusion: Non-attendance can depend on several factors that influence each other and small differences was seen between men and women. The invitation letter could affect the participation in some cases.

Aneurisma de Aorta Abdominal (AAA) é definido como uma dilatação localizada e permanente da parede arterial, geralmente com ocorrência entre as artérias renais e as ilíacas, como conseqüência do enfraquecimento dessa parede ou devido a uma solicitação anormal sobre sua estrutura normal. Essa afecção acomete principalmente a população idosa acima de 65 anos de idade, tendo como principais fatores de risco: tabagismo, hipertensão arterial, histórico familiar e doença obstrutiva crônica pulmonar. A prevalência está aumentando nos últimos anos, havendo uma duplicação dos casos diagnosticados nos Estados Unidos (Bonamigo e Von Ristow, 1999). Hoje o AAA é a 13ª causa de morte nos Estados Unidos, em homens com mais de 65 anos e no caso de aneurisma roto, é a 3ª causa de morte súbita nos Estados Unidos. A mortalidade global do AAA roto está em torno de 80% nos países que têm verificação sistemática e compulsória da causa de óbitos. Isto ocorre devido ao fato de uma hemorragia substancial intra-abdominal geralmente ser acompanhada de atraso no transporte e diagnóstico, e da necessidade de cirurgia de emergência em pacientes idosos que, freqüentemente, tem uma significativa comorbidade renal e cardiopulmonar. Acredita-se que a formação e o crescimento do aneurisma de aorta abdominal são acompanhados do crescimento da tensão na parede da aorta e/ou de uma diminuição da capacidade do tecido de suportar tal tensão. A ruptura ocorre quando a tensão atuante na parede excede a tensão que pode ser suportada pelo tecido. O risco de ruptura aumenta com o crescimento do tamanho do aneurisma, da tensão na parede e é agravado quando associado à hipertensão arterial. No estudo foram obtidos dados morfológicos da região torácica de um paciente com a utilização de tomografia computadorizada multi-fatias. Essas imagens DICOM (Comunicação de Imagens Digitais em Medicina) foram tratadas para selecionar apenas a região de interesse, obtendo-se um modelo tridimensional da aorta infra-renal e artérias ilíacas. A partir daí, foi confeccionado um modelo físico com a utilização de prototipagem rápida. Um simulador cardiovascular controlado por computador foi desenvolvido com o intuito de replicar características fisiológicas e patológicas do sistema cardiovascular humano. Esse modelo de aneurisma foi utilizado para simulação em bancada experimental, onde é possível reproduzir alguns parâmetros como pressão, fluxo, temperatura, resistência e complacência vascular. Também foi gerado um modelo computacional onde os parâmetros obtidos na simulação in vitro foram utilizados como condição de contorno inicial para o estudo computacional. Foram adotados padrões normotenso e hipertenso, e os resultados computacionais e experimentais foram analisados e comparados. O trabalho propõe uma metodologia que possibilite a obtenção de dados anatômicos e hemodinâmicos relativos ao segmento arterial acometido pela afecção, com o objetivo de fornecer informações adicionais no diagnóstico do aneurisma de aorta. / Abdominal Aortic Aneurysm (AAA) is defined as a focal and permanent dilatation of the arterial wall, most often occurring in between the renal and iliac arteries, as consequence of arterial wall weakness or because of an abnormal solicitation of that normal structure. This disease primarily affects elderly population over 65 years of age, and the most important risk factors are smoking, hypertension, family history and chronic obstructive pulmonary disease. In the last years, the prevalence is rising up almost twice the diagnosed cases in the United States (Bonamigo and Von Ristow, 1999). Nowadays, AAA is the thirtieth cause of death in the United States, in the elderly masculine population over 65 years of age, and in case of ruptured aneurysm, it is the third cause of sudden death in the United States. The overall mortality rate is about 80% in countries with systematic and compulsory evaluation of death cause. This is due to the fact that substantial intra-abdominal hemorrhage is often accompanied by delays in transport and diagnoses, and the need for emergency surgery in elderly patients that frequently have significant renal and cardiopulmonary comorbidity. It is suggested that the formation and expansion of the AAA are accompanied by wall stress increasing and / or decreasing in the tissue capacity to withstand this stress. The rupture occurs when the wall stress exceed the stress the tissue can accept. The risk of rupture increases with aneurysm expansion, wall stress increasing and it is exacerbated when associated with arterial hypertension. In the present work, morphological data from thoracic region of the patient was acquired by using multi-slice CT (Computed Tomography). These DICOM images had been treated to select only the interest region, getting a three-dimensional infra-renal aortic and iliac model. Then, it was made a physical model by using rapid prototyping. This model was used for in vitro experimentation in a computer controlled mock system, in which it is possible to replicate physiological and pathological characteristics of human being cardiovascular system. Some parameters such as pressure, flow, temperature, vascular resistance and compliance can be reproduced by the use of a mock circulatory system. These parameters were used as initial boundary conditions in order to calibrate a computational model. It was adopted normotensive and hypertensive patterns and computational and experimental results were analyzed and compared. The paper proposes a methodology which allows the acquisition of anatomical and hemodynamic data on the vessel segment affected by the pathology, with the goal of providing additional information in the diagnosis of aortic aneurysm.

Aneurisma de Aorta Abdominal (AAA) é definido como uma dilatação localizada e permanente da parede arterial, geralmente com ocorrência entre as artérias renais e as ilíacas, como conseqüência do enfraquecimento dessa parede ou devido a uma solicitação anormal sobre sua estrutura normal. Essa afecção acomete principalmente a população idosa acima de 65 anos de idade, tendo como principais fatores de risco: tabagismo, hipertensão arterial, histórico familiar e doença obstrutiva crônica pulmonar. A prevalência está aumentando nos últimos anos, havendo uma duplicação dos casos diagnosticados nos Estados Unidos (Bonamigo e Von Ristow, 1999). Hoje o AAA é a 13ª causa de morte nos Estados Unidos, em homens com mais de 65 anos e no caso de aneurisma roto, é a 3ª causa de morte súbita nos Estados Unidos. A mortalidade global do AAA roto está em torno de 80% nos países que têm verificação sistemática e compulsória da causa de óbitos. Isto ocorre devido ao fato de uma hemorragia substancial intra-abdominal geralmente ser acompanhada de atraso no transporte e diagnóstico, e da necessidade de cirurgia de emergência em pacientes idosos que, freqüentemente, tem uma significativa comorbidade renal e cardiopulmonar. Acredita-se que a formação e o crescimento do aneurisma de aorta abdominal são acompanhados do crescimento da tensão na parede da aorta e/ou de uma diminuição da capacidade do tecido de suportar tal tensão. A ruptura ocorre quando a tensão atuante na parede excede a tensão que pode ser suportada pelo tecido. O risco de ruptura aumenta com o crescimento do tamanho do aneurisma, da tensão na parede e é agravado quando associado à hipertensão arterial. No estudo foram obtidos dados morfológicos da região torácica de um paciente com a utilização de tomografia computadorizada multi-fatias. Essas imagens DICOM (Comunicação de Imagens Digitais em Medicina) foram tratadas para selecionar apenas a região de interesse, obtendo-se um modelo tridimensional da aorta infra-renal e artérias ilíacas. A partir daí, foi confeccionado um modelo físico com a utilização de prototipagem rápida. Um simulador cardiovascular controlado por computador foi desenvolvido com o intuito de replicar características fisiológicas e patológicas do sistema cardiovascular humano. Esse modelo de aneurisma foi utilizado para simulação em bancada experimental, onde é possível reproduzir alguns parâmetros como pressão, fluxo, temperatura, resistência e complacência vascular. Também foi gerado um modelo computacional onde os parâmetros obtidos na simulação in vitro foram utilizados como condição de contorno inicial para o estudo computacional. Foram adotados padrões normotenso e hipertenso, e os resultados computacionais e experimentais foram analisados e comparados. O trabalho propõe uma metodologia que possibilite a obtenção de dados anatômicos e hemodinâmicos relativos ao segmento arterial acometido pela afecção, com o objetivo de fornecer informações adicionais no diagnóstico do aneurisma de aorta. / Abdominal Aortic Aneurysm (AAA) is defined as a focal and permanent dilatation of the arterial wall, most often occurring in between the renal and iliac arteries, as consequence of arterial wall weakness or because of an abnormal solicitation of that normal structure. This disease primarily affects elderly population over 65 years of age, and the most important risk factors are smoking, hypertension, family history and chronic obstructive pulmonary disease. In the last years, the prevalence is rising up almost twice the diagnosed cases in the United States (Bonamigo and Von Ristow, 1999). Nowadays, AAA is the thirtieth cause of death in the United States, in the elderly masculine population over 65 years of age, and in case of ruptured aneurysm, it is the third cause of sudden death in the United States. The overall mortality rate is about 80% in countries with systematic and compulsory evaluation of death cause. This is due to the fact that substantial intra-abdominal hemorrhage is often accompanied by delays in transport and diagnoses, and the need for emergency surgery in elderly patients that frequently have significant renal and cardiopulmonary comorbidity. It is suggested that the formation and expansion of the AAA are accompanied by wall stress increasing and / or decreasing in the tissue capacity to withstand this stress. The rupture occurs when the wall stress exceed the stress the tissue can accept. The risk of rupture increases with aneurysm expansion, wall stress increasing and it is exacerbated when associated with arterial hypertension. In the present work, morphological data from thoracic region of the patient was acquired by using multi-slice CT (Computed Tomography). These DICOM images had been treated to select only the interest region, getting a three-dimensional infra-renal aortic and iliac model. Then, it was made a physical model by using rapid prototyping. This model was used for in vitro experimentation in a computer controlled mock system, in which it is possible to replicate physiological and pathological characteristics of human being cardiovascular system. Some parameters such as pressure, flow, temperature, vascular resistance and compliance can be reproduced by the use of a mock circulatory system. These parameters were used as initial boundary conditions in order to calibrate a computational model. It was adopted normotensive and hypertensive patterns and computational and experimental results were analyzed and compared. The paper proposes a methodology which allows the acquisition of anatomical and hemodynamic data on the vessel segment affected by the pathology, with the goal of providing additional information in the diagnosis of aortic aneurysm.

<p>By applying a segmentation procedure to two different sets of computed tomography scans, two geometrical models of the abdominal aorta, containing one inlet and two outlets have been constructed. One of these depicts a healthy blood vessel while the other displays one afflicted with a Abdominal Aortic Aneurysm. </p><p>After inputting these geometries into the computational dynamics software FLUENT, six simulations of laminar, stationary flow of a fluid that was assumed to be Newtonian were performed. The mass flow rate across the model outlet boundaries was varied for the different simulations to produce a basis for a parameter analysis study. </p><p>The segmentation data was also used as input data to a surface description procedure which produced not only the surface itself, but also the first and second directional derivatives in every one of its defining spatial data points. These sets of derivatives were followingly applied in an additional procedure that calculated values of Gaussian curvature. </p><p>A parameter variance analysis was carried out to evaluate the performance of the surface generation procedure. An array of resultant surfaces and surface directional derivatives were obtained. Values of Gaussian curvature were calculated in the defining spatial data points of a few selected surfaces. </p><p>The curvature values of a selected data set were visualized through a contour plot as well as through a surface map. Comparisons between the curvature surface map and one wall shear stress surface map were made.</p>

Crossing of stent graft limbs during endovascular aneurysm repair (EVAR) is often used to assist cannulation and prevent graft kinking when the aortic bifurcation is widely splayed. Little has been reported about the implications of cross-limb EVAR, especially in comparison to conventional EVAR. Using computational fluid dynamics, this work numerically examines the hemodynamic differences between these two out-of-plane stent graft configurations against a planar configuration commonly found in literature. Predicted values of displacement force, wall shear stress, and oscillatory shear index were similar between the out-of-plane configurations. The planar configuration predicted similar wall shear stress values, but significantly lower displacement forces than the out-of-plane configurations. These results suggest that the hemodynamic safety of cross-limb EVAR is comparable to conventional EVAR. However, a study of clinical outcomes may reveal reduced thrombosis incidence and long-term structural implications for the stent graft in cross-limb EVAR.

Crossing of stent graft limbs during endovascular aneurysm repair (EVAR) is often used to assist cannulation and prevent graft kinking when the aortic bifurcation is widely splayed. Little has been reported about the implications of cross-limb EVAR, especially in comparison to conventional EVAR. Using computational fluid dynamics, this work numerically examines the hemodynamic differences between these two out-of-plane stent graft configurations against a planar configuration commonly found in literature. Predicted values of displacement force, wall shear stress, and oscillatory shear index were similar between the out-of-plane configurations. The planar configuration predicted similar wall shear stress values, but significantly lower displacement forces than the out-of-plane configurations. These results suggest that the hemodynamic safety of cross-limb EVAR is comparable to conventional EVAR. However, a study of clinical outcomes may reveal reduced thrombosis incidence and long-term structural implications for the stent graft in cross-limb EVAR.

By applying a segmentation procedure to two different sets of computed tomography scans, two geometrical models of the abdominal aorta, containing one inlet and two outlets have been constructed. One of these depicts a healthy blood vessel while the other displays one afflicted with a Abdominal Aortic Aneurysm. After inputting these geometries into the computational dynamics software FLUENT, six simulations of laminar, stationary flow of a fluid that was assumed to be Newtonian were performed. The mass flow rate across the model outlet boundaries was varied for the different simulations to produce a basis for a parameter analysis study. The segmentation data was also used as input data to a surface description procedure which produced not only the surface itself, but also the first and second directional derivatives in every one of its defining spatial data points. These sets of derivatives were followingly applied in an additional procedure that calculated values of Gaussian curvature. A parameter variance analysis was carried out to evaluate the performance of the surface generation procedure. An array of resultant surfaces and surface directional derivatives were obtained. Values of Gaussian curvature were calculated in the defining spatial data points of a few selected surfaces. The curvature values of a selected data set were visualized through a contour plot as well as through a surface map. Comparisons between the curvature surface map and one wall shear stress surface map were made.

Abdominal aortic aneurysm (AAA) is a chronic inflammatory disease with no available pharmacological treatment. AAA formation reduces the structural integrity of the vessel and increases the susceptibility to rupture. The inflammatory response within human aneurysmal tissue is characterized by increased expression of cyclooxygenase-2 (COX-2). Similarly, in a mouse model of the disease induced by chronic Angiotensin II (AngII) infusion, we have shown that COX-2 expression in the abdominal aortic smooth muscle layer increases early in the development of the disease. Furthermore, genetic or pharmacological inactivation of COX-2 prior to disease initiation reduces AAA incidence. The current study utilized nonhyperlipidemic mice to determine the effectiveness of COX-2 inhibition initiated after AAA formation. COX-2 inhibitor treatment was initiated 5 days after beginning the AngII infusion, a time-point where significant aneurysmal pathology is observed. COX-2 inhibition with celecoxib significantly reduced the incidence as well as severity of AAAs as compared to the control group. Celecoxib treatment also protected the mice from aortic rupture and death. AAA development is characterized by degradation of the aortic smooth muscle layer with loss of the contractile phenotype. We found that the effectiveness of celecoxib was associated with significantly increased mRNA expression of alpha-actin, SM22alpha and desmin, all of which are markers of a differentiated smooth muscle cell phenotype. Celecoxib treatment also decreased mRNA expression of a marker of dedifferentiated smooth muscle (hyaluronic acid synthase 2). We also examined the role of altered expression of COX-2 in the increased susceptibility of the abdominal segment to AAA formation. We found a prolonged and greater induction of COX-2 in the abdominal aortic smooth muscle layer in contrast to a transient induction of COX-2 in the other regions of the aorta throughout disease progression. Overall, these findings suggest that COX-2 plays an important role in AAA development in mice, and COX-2 inhibition with celecoxib attenuates progression of aneurysm development by maintaining a differentiated phenotype in abdominal aortic smooth muscle cells.

Abdominal aortic aneurysm (AAA) is a disease of the aorta characterized by pathological remodeling and progressive weakening of the vessel resulting in the increased risk of rupture and sudden death. In a mouse model of the disease induced by chronic Angiotensin II (AngII) infusion, progression of AAAs is associated with reduced differentiation of smooth muscle cells (SMCs) at the site of lesion development. In the mouse model, the effectiveness of cyclooxygenase-2 (COX-2) inhibition for attenuating AAA progression is associated with maintenance of a differentiated SMC phenotype. However, the safety of COX-2 inhibitors is currently in question due to the increased risk of adverse cardiovascular events. Thus, it is crucial to identify mediators downstream of COX-2 that may provide new targets for treatment of this disease. Recent studies in humans and mouse models have suggested that the microsomal prostaglandin E synthase (mPGES-1) enzyme, which acts downstream of COX-2, may also be involved in the pathogenesis of the disease. We hypothesized that increased prostaglandin E2 (PGE2) synthesis resulting from the induction of both COX-2 and mPGES-1 may result in reduced differentiation of SMCs, and that disruption of this pathway would preserve the differentiated phenotype. To test this hypothesis, human aortic smooth muscle cells (hASMCs) were utilized to examine the effects of a variety of agents involved in AAA development and the COX-2 pathway. My findings suggest that one of the effects of exposing hASMCs to AngII involves a specific induction of mPGES-1 expression. Furthermore, although different COX-2-derived products may have opposing effects, mPGES-1-derived PGE2 may be the primary prostanoid synthesized by SMCs which functions to attenuate differentiation. Therefore, mPGES-1 inhibition may provide inhibition of PGE2 that is more specific than COX-2 inhibitor treatment and may serve as a therapeutic target for attenuating AAA progression by maintaining a differentiated SMC phenotype.

The etiology of abdominal aortic aneurysms (AAA) is characterized by localized extracellular matrix remodeling and vessel dilation. Population-based studies have shown that AAA account for nearly 1% of all deaths. This thesis seeks to identify the earliest molecular and biomechanical determinants of aneurysm formation. Our initial motivator was the lack of information defining the underlying mechanisms of AAA formation. We used isolated vessel testing and histological analysis to study the mechanical and morphological evolution of AAA. These factors were measured in murine models of reproducible AAA formation. From this study, we determined 1) that molecular events precede mechanical events in AAA progression and 2) aortic circumferential mechanics are well conserved during AAA pathogenesis. Next we sought to explore the mechanistic link between oxidative stress and AAA development. To determine this relationship we used isolated vessel testing as well as measurement of aortic residual circumferential strain. To isolate the role of oxidative stress in these studies we used a line of transgenic mice with vascular smooth muscle cell-specific overexpression of the antioxidant catalase. The results of this study suggest that oxidative stress-mediated elastin degeneration within the aortic media is etiologic of altered aortic mechanics. Lastly, we sought to determine the independent mechanical contribution of the aortic adventitia and media tunica to overall aortic behavior. To accomplish this goal we compared the circumferential and axial mechanical behavior of aortas with and without collagenase treatment. The data demonstrated that the adventitia regulates the circumferential behavior of the aorta by preventing overstretch and the media regulates the axial behavior by maintaining tensile loading. This thesis demonstrates 1) that detecting early aneurysm progression in the form of mechanical or geometric changes may miss the window in which aneurysm pathology may be potentially reversed, 2) that mitigating oxidative stress within the aortic wall may provide protection against AAA, and 3) the adventitia is an important load bearing constituent of the arterial wall and plays a role in vascular adaptation to altered mechanical states. Overall our results impact understanding of early aneurysmal pathogenesis and may facilitate the development of preventative therapies for AAA progression and rupture.